[robbiegriggs]

After doing research on the site and acquiring some equipment from members over the last month, I’ve reached a point where I could use some advice. The vehicle I’m working with is a 2016 BMW 228i convertible.

Here are my goals and parameters:

• Maintain OEM look of the car, including using existing speaker locations and utilizing the driver-side recess in the trunk for the sub to retain space for luggage;
• Retain functionality of HU/Nav controls with the system;
• Attain a good balance of SQ and volume, as this is my daily driver, I’m not going to be entering any competitions, and I like to listen to a variety of music;
• Build a system that is reliable and relatively easy to use, because I’m not a tinkerer (at least, not at this point!);
• Stick to a budget of around $3k, if possible, for remaining equipment and install (originally, I was going to do the install myself, but the more I’ve learned the more I’ve realized that what I want is unachievable given my competence and desired timeline).

Thus far, I’ve decided on a three-way active front stage and I’m planning on putting a sub in the trunk. Here’s the equipment I’ve acquired:

• Audiofrog GB 10 (factory location is a sail panel)
• Audiofrog GB 40 (door)
• Audio-Development W800 NEOs for midbass (underseat)
• MMATS Hifi 4250d for the NEOs and a sub

So, here are my primary questions:

• Should I purchase separate DSP, MOST integration, and Amp, or could I combine one or more of these to save space? I'm intrigued, for example, by the mObridge BMW MOST25 8.1.1, but I recognize that would be overkill when combined with the four channel MMATS.
• If I can combine components, would a Helix P Six DSP MK2 and Helix SDMI25 be a good solution?
• If I should separate all these components, what amps should I consider for the mids and tweets? Stick with MMATS and go for the Hifi 6150D, leaving the possibility of rear fill and an extra sub in the future? Or go with another four channel amp?
• Given separate components and that I’m no expert tuner and won’t be one anytime soon, should I consider the miniDSP with Dirac Live over a Helix DSP? If I’m going to be trusting a pro with the tune, at least initially, what should I give him to work with?
• How should I handle the source? For the sake of portability and simplicity, I’d like to use a streaming service like Tidal and their MQA files. I have an IPhone XR, which I could use. But if there are advantages to having a dedicated player, I’m open to that. What is the simplest way of getting a high quality signal to the DSP while retaining some flexibility, if using a phone or DAP? I’ve seen a variety of threads on the site surrounding these things, and I recognize that not playing lossless files defeats the whole purpose here.
• Sub enclosure and sub? To save space, I’d like to use something like what MusicarNW does with their OE look enclosures, but unfortunately their coupe version (F22) doesn’t fit the convertible (F23). People on the BMW forums have used this guy Visual Ice in the UK, who sells enclosures on Ebay. Perhaps I’m just at the mercy of a local installer who can fabricate a box for me.
• Assuming one of these enclosure is possible, could I run a 12”Audiofrog sub, or would I be limited to a 10"? I believe the space would be sufficient for a sealed enclosure. Are there any advantages, given my amp options above or other possibilities, to running the 2ohm over the 4ohm for the sub?

In any case, having written all of this, I’m recognizing that there are a ton of gaps. I’m a novice here, so I apologize for that. But it is what it is.

Thanks in advance for any advice you have for me!

 

[DaveG]

What is your factory system? Is it the "M Package" option 676 system?

 

[robbiegriggs]

Sorry. It has the S674A sound system, which I'm now realizing may not have MOST output.

 

[GoldRiver]

Where is the sound deadening in your budget?
Why not just get the Helix with integrated amp?
Tidal is fine.
How much space do you have for a sub enclosure? Look up recommended enclosure sizes for the subs you want.

 

[4saleongrcraigslist]

DSP + AMP
Helix V8 ($1200) or V12 ($2000) both have DSP

Director (This will allow presets for a single seat or dual seat sound stage, etc.) ($400) Can add it later as well.

Bluetooth Module add-on you plug into the V8 or V12. This will allow your phone to play directly into DSP whenever you want high quality tunes and not fk with factory system.

Subwoofer
Get a recognized (i.e. accomplished) builder to make a custom Sub Woofer Box that is tuned for what you like to hear. Buy quality sub, power it well.

Factory Speakers
Use your factory speakers. You have a budget replace them later.

Tuner (Recognized Person Known for Tuning)
Spend money on someone that knows how to tune your car (Single, Dual & Center Channel) with Helix DSP, New Sub & Existing Speakers.

When you have more $$$$ replace speakers with better ones and have the car re-tuned. In the mean time have the Helix Amp drive the factory speakers.

I bet this will blow your mind given your budget.

 

[robbiegriggs]

Where is the sound deadening in your budget?
Why not just get the Helix with integrated amp?
Tidal is fine.
How much space do you have for a sub enclosure? Look up recommended enclosure sizes for the subs you want.

I was including sound deadening in the cost of the install, but I honestly have know idea how much that will cost.
Someone pointed out that the Helix P Six only has one stereo out, which would prevent me from running both the midbass and the sub with the MMATS Hifi 4250D.
I believe, with an enclosure fitted in the space behind the driver-side wheel well, I can get 1 cubic foot, which would be enough for the Audiofrog 12 that requires 0.75-1.27 cubic feet.

 

[robbiegriggs]

DSP + AMP
Helix V8 ($1200) or V12 ($2000) both have DSP

Director (This will allow presets for a single seat or dual seat sound stage, etc.) ($400) Can add it later as well.

Bluetooth Module add-on you plug into the V8 or V12. This will allow your phone to play directly into DSP whenever you want high quality tunes and not fk with factory system.

Subwoofer
Get a recognized (i.e. accomplished) builder to make a custom Sub Woofer Box that is tuned for what you like to hear. Buy quality sub, power it well.

Factory Speakers
Use your factory speakers. You have a budget replace them later.

Tuner (Recognized Person Known for Tuning)
Spend money on someone that knows how to tune your car (Single, Dual & Center Channel) with Helix DSP, New Sub & Existing Speakers.

When you have more $$$$ replace speakers with better ones and have the car re-tuned. In the mean time have the Helix Amp drive the factory speakers.

I bet this will blow your mind given your budget.

Thanks for this advice. If I were starting from scratch, I probably would have gone this route. But I've caught the itch and started purchasing equipment. And I started, perhaps foolishly, with the speakers.

 

[jimmydee]

First thing's first... figure out if your system has a MOST connection.

 

[robbiegriggs]

First thing's first... figure out if your system has a MOST connection.

Update: I've confirmed that this system does not have a MOST connection. It is possible to do a MOST conversion by running a cable and doing some coding with the HU. I'm not sure it is worth the trouble, though.

So, assuming no MOST, I'll be working with separate sources. What is the simplest/cleanest way to do that? Helix DSP, Helix Director, and Helix HEC USB?

 

[dumdum]

If you can get the most network enabled and added it will offer a better signal vs using speakers after the amplifier

that’s what I’d be doing

 

[jimmydee]

You are still able to tap into the vehicle's MOST network... but it's definitely not as simple as it would be, if you had an existing OEM amp in place.
Also, you would need a BMW dealer, or an aftermarket shop that has a BMW coding tool, to re-code your system so it activates the MOST audio output.

If you're not going to integrate into the vehicle's OEM head unit (through MOST); then yes, use a Helix DSP, Director, and HEC-USB.
Store and source all your audio files on a Fiio (or something like that), and use it that way.

From a sound quality perspective; you'll actually get better SQ going this route...
But from a convenience perspective; it's easier to use the head unit / MMI to source and select your music.

 

[robbiegriggs]

You are still able to tap into the vehicle's MOST network... but it's definitely not as simple as it would be, if you had an existing OEM amp in place.
Also, you would need a BMW dealer, or an aftermarket shop that has a BMW coding tool, to re-code your system so it activates the MOST audio output.

If you're not going to integrate into the vehicle's OEM head unit (through MOST); then yes, use a Helix DSP, Director, and HEC-USB.
Store and source all your audio files on a Fiio (or something like that), and use it that way.

From a sound quality perspective; you'll actually get better SQ going this route...
But from a convenience perspective; it's easier to use the head unit / MMI to source and select your music.

Thanks for this. I think I'm going to forgo the MOST retrofit and go the second route.

With that said, in case anyone else finds this thread in the future, I'm linking to a post that is related to this kind of integration: DIY: Individual "M" Audio/Enhanced Premium Sound (Logic 7) Retrofit